#region Copyright & License Information
/*
 * Copyright 2007-2020 The OpenRA Developers (see AUTHORS)
 * This file is part of OpenRA, which is free software. It is made
 * available to you under the terms of the GNU General Public License
 * as published by the Free Software Foundation, either version 3 of
 * the License, or (at your option) any later version. For more
 * information, see COPYING.
 */
#endregion

using System.Collections.Generic;
using System.Diagnostics.CodeAnalysis;
using System.Linq;
using OpenRA.Mods.Common.UpdateRules.Rules;

namespace OpenRA.Mods.Common.UpdateRules
{
	public class UpdatePath
	{
		// Define known update paths from stable tags to the current bleed tip
		//
		// This file should be maintained separately on prep branches vs bleed.
		// The bleed version of this file should ignore the presence of the prep branch
		// and list rules from the playtest that forked the prep branch and current bleed.
		// The prep branch should maintain its own list of rules along the prep branch
		// until the eventual final release.
		//
		// When a final release has been tagged the update paths from the prep branch
		// can be merged back into bleed by replacing the forking-playtest-to-bleed path
		// with the prep playtest-to-playtest-to-release paths and finally a new/modified
		// release-to-bleed path.
		[SuppressMessage("StyleCop.CSharp.ReadabilityRules", "SA1118:ParameterMustNotSpanMultipleLines",
			Justification = "Extracting update lists to temporary variables obfuscates the definitions.")]
		static readonly UpdatePath[] Paths =
		{
			new UpdatePath("release-20191117", "release-20200202", new UpdateRule[]
			{
				new ReplaceAttackTypeStrafe()
			}),

			new UpdatePath("release-20200202", "release-20200503", new UpdateRule[]
			{
				new RemoveYesNo(),
				new RemoveInitialFacingHardcoding(),
				new RemoveAirdropActorTypeDefault(),
				new RenameProneTime(),
				new RemoveWithPermanentInjury(),
				new AddResourceRenderer(),
				new ReformatChromeProvider(),
				new RenameSpins(),
				new CreateScreenShakeWarhead(),
				new RenameRallyPointPath(),
			}),

			new UpdatePath("release-20200503", new UpdateRule[]
			{
				// Bleed only changes here
				new AddPipDecorationTraits(),
				new ModernizeDecorationTraits(),
				new RenameHealCrateAction(),
				new RenameInfiltrationNotifications(),
				new MoveClassicFacingFudge(),
				new RenameWithNukeLaunch(),
				new SpawnActorPowerDefaultEffect(),
				new RemoveConditionManager(),
				new ConvertSupportPowerRangesToFootprint(),
				new UpdateTilesetColors(),
			})
		};

		public static IEnumerable<UpdateRule> FromSource(ObjectCreator objectCreator, string source, bool chain = true)
		{
			// Use reflection to identify types
			var namedType = objectCreator.FindType(source);
			if (namedType != null && namedType.IsSubclassOf(typeof(UpdateRule)))
				return new[] { (UpdateRule)objectCreator.CreateBasic(namedType) };

			var namedPath = Paths.FirstOrDefault(p => p.source == source);
			return namedPath != null ? namedPath.Rules(chain) : null;
		}

		public static IEnumerable<string> KnownPaths { get { return Paths.Select(p => p.source); } }
		public static IEnumerable<string> KnownRules(ObjectCreator objectCreator)
		{
			return objectCreator.GetTypesImplementing<UpdateRule>().Select(t => t.Name);
		}

		readonly string source;
		readonly string chainToSource;
		readonly UpdateRule[] rules;
		UpdatePath(string source, UpdateRule[] rules)
			: this(source, null, rules) { }

		UpdatePath(string source, string chainToSource, UpdateRule[] rules)
		{
			this.source = source;
			this.rules = rules;
			this.chainToSource = chainToSource;
		}

		IEnumerable<UpdateRule> Rules(bool chain = true)
		{
			if (chainToSource != null && chain)
			{
				var child = Paths.First(p => p.source == chainToSource);
				return rules.Concat(child.Rules(chain));
			}

			return rules;
		}
	}
}